completionTag=0x7fff06aee670 "") at pquery.c:816 #7 0x0000000000750944 in exec_simple_query (query_string=0x17e90b0 "drop table t1;") at postgres.c:1045 #8 0x0000000000754967 in PostgresMain (argc=1, argv=0x1784148, dbname=0x1784130 "wzy", username=0x1784110 "xiaochu.yh") at postgre...
CREATE TABLE - SQL Command DELETE - SQL Command DELETE TAG Command DROP TABLE Command INDEX Command INSERT - SQL Command SELECT - SQL Command SET ANSI Command SET BLOCKSIZE Command SET COLLATE Command SET DELETED Command SET EXACT Command SET EXCLUSIVE Command SET NULL Command SET PATH Command ...
Use the TRUNCATE TABLE command (deletes only the data inside the table): 当我们只想将表内的数据做完成清楚而保留其内部结构的话,可以使用TRUNCATE TABLE命令(仅仅删除表中的数据) TRUNCATE TABLE table_name
Sometimes Microsoft SQL Server tables are created that are no longer needed. To help keep the SQL relational database clean there is a need to delete these unneeded tables. In this tutorial we look at how to delete a table using the DROP TABLE SQL command. Solution We'll look at the syn...
分析:truncate table 在功能上与不带where的delete语句相同:二者均删除表中的全部行。 但truncate table比delete速度快,且使用的系统和事务日志资源少。delete语句每次删除一行,并在事务日志中为所删除的每行记录 一项。truncate table通过释放存储表数据所用的数据页来删除数据,只在事务日志中记录页的释放。
17 SQL Statements: DROP LIBRARY to DROP SYNONYM 18 SQL Statements: DROP TABLE to LOCK TABLE DROP TABLE DROP TABLESPACE DROP TABLESPACE SET DROP TRIGGER DROP TYPE DROP TYPE BODY DROP USER DROP VIEW EXPLAIN PLAN FLASHBACK DATABASE FLASHBACK TABLE ...
DROP TABLE `content`, `content_admin`, `content_cat`, `content_cmt_post`; The above command will delete four tables. Dropping a unique constraints We can use DROP sql command to remove unique constraints associated to any column, here is an example. ...
TheDROP TABLEcommand deletes a table in the database. The following SQL deletes the table "Shippers": Example DROPTABLEShippers; Try it Yourself » Note:Be careful before deleting a table. Deleting a table results in loss of all information stored in the table!
The command consists of: ThePREPAREstatement. Prepares the SQL statement stored in the@droptoolvariable. It sets up the command so it can be executed. TheEXECUTEstatement. Executes theDROP TABLEcommand, which deletes the specified tables.
SQL - DROP Table - SQL provides command to DROP an existing table completely in a database. Once SQL DROP command is issued then there is no way back to recover the table including its data, so be careful before issuing this command in production system.